CINCINNATI (AP) — Scott Rolen’s left shoulder feels much better when he drives a car, a sign that his latest surgery has worked.

When the 36-year-old third baseman can return is still unclear. So are the Cincinnati Reds’ plans for filling in his spot, one that took a new twist Monday when Yonder Alonso took ground balls at the position.

Rolen had surgery last Wednesday to clean out his left shoulder, which has bothered him all season. He’s limited to working on his range of motion, a small step that’s brought encouragement.

Already, the shoulder feels a lot better.

“Right now, it’s freeing up a lot of motion,” Rolen said on Monday, before getting treatment. “I feel like my shoulder’s working correctly. It’s been a relief.

“Just little stuff, like driving a car. I’m a better driver now because my neck’s not locked up.”

The Reds expect Rolen to be out for at least a month. They’ll have to decide when he’s healthy whether they want to play him again in what has quickly become a lost season. The defending NL Central champions were 9 1/2 games out of first place heading into the start of their series against Colorado on Monday night.

Rolen hesitated when asked whether he’ll be back this season. He’s under contract for 2012 with a base salary of $6.5 million.

“Well, I mean, I certainly have aspirations of returning this year,” Rolen said. “I think they have aspirations of me returning this year. I’m not even a week out of surgery.

“We’re going to rehab it and do the correct thing. When that time comes, we’ll see where we are and play some baseball. That’s the plan right now. I don’t have a timeline.”

In the meantime, Alonso could get a chance to try the position. The former first-round pick is stuck behind National League MVP Joey Votto at first base, and the Reds are trying to find another spot that suits him.

Alonso played some games in left field at Triple-A this season and was given a tryout there last week. He misplayed several balls during a road trip to Houston and Chicago, ending the experiment.

Asked on Monday if Alonso will be back in left field again, manager Dusty Baker said, “I don’t know. Not in the near future.”

Instead, the first-round pick from 2008 took ground balls at third base before Monday’s game, working with bench coach Chris Speier.

“It’s something I thought of about a week ago,” Baker said. “I talked to him and he said he signed (with the Reds) as a third baseman, so we’ll see. We’re trying to figure out a way to get him in the lineup.”

Alonso was one of Triple-A Louisville’s top hitters when he was called up on July 26. He’s gone 8 for 16 with a homer, limited by the lack of an everyday position.

Alonso embraced the chance to play third base, noting he played there before he was drafted by the Reds.

“I always took ground balls there, even when I was in Triple-A,” Alonso said. “I think it comes pretty naturally to me. It’s not as new as left field. It’s the infield — that’s where I’ve played all my life.

“Obviously first base is locked down completely. I think they’re trying to get my bat in the lineup.”

I feel pretty good at third base. As long as I’m adequate and good enough to play out there, which I think I am, hopefully they’ll give me a shot.”